Trains accelerate incredibly slowly and often have a single gear that is optimised for high speed. Similar to trying to pull away in your car in too high of a gear this makes trains really slow and takes along time for them to hit their high speed.
Most cars will often have 4 (for very old cars) – 6 gears to keep acceleration smooth and fast whilst still being efficient at high speed but trains don’t.
I get that electric motors have all of the torque available at low RPMs whilst ICE only have full power at a high rpm but wouldn’t gears still allow trains to get to higher speeds quicker?
In: Engineering
The “torque from the start” isn’t universally true for all types of electric motors, and it’s also not entirely accurate. Many types of electric motors actually have a lot more torque available at a standstill, while others only reach their maximum torque once they spin up. Ceiling fans for example have barely any torque from a standstill, which is why they take so long to spin up and why you can easily stall them.
However, you are not wrong: For maximum acceleration, electric motors can benefit from a gearbox in order to keep the motor running in its optimum RPM range. Porsche does that with their new electric sports car. However, this adds weight and complexity, and electric trains usually have plenty of acceleration anyways.
Latest Answers